My wife and I attended TEDx Mile High – “Ideas Unbridled” in Denver yesterday. I measured my heart rate variability (HRV) during each speech and on the conclusion of each rated it on how much I thought I enjoyed it. I wanted to compare my mental rating of the speeches and my physiological reaction to the same. Would the reactions match? Or was my physiology detached from the proceedings and my consumption of the speech was only a mental exercise?
I listened to twelve speeches over the course of the afternoon. The general arc was that the first four speakers I did not connect with, the fifth was a very inspiring speech, the next few were interesting, the last four were really good with the final one being absolutely great. So if I were to draw out my enjoyment curve by hand, it would look something like this:
My wife and I discussed the speeches as we walked home. I remember telling her I liked the middle spike speaker (Eric Kornacki) and the final speaker (Teju Ravilochan). I also mentioned that I liked some of the other speakers but I referred to them by topic rather than by name. I used descriptors “the Polar Vortex guy” or “the Twitter guy” and “the Visual Mantra Woman.” That was my subjective memory at work.
I had rated each speaker immediately after their speech on a scale of 1 to 10, therefore I had data recording my immediate reaction to each speech. Here is that curve:
During the actual experience of the speeches I had enjoyed remarks by Jesse Zhang and Chris Hansen nearly as much as Eric and Teju’s speeches, but because they sat in proximity to each other and Teju I could not recall them as well.
Finally, I pulled the data on my HRV, scaled it so I could lay it side by side with my mental assessment and you see that graph here:
My heart rate variability tracked closely with my mental assessment of each speech. The Pearson correlation between the two measurement arrays is .84, meaning my mental assessment of enjoyment had a very strong relationship with my physiological reaction to the speeches. It appears my enjoyment of the lineup of speakers was gradually increasing although my mental assessment was more extreme at the moment.
So the physiology and the mental assessment track together. When I am delighted, entertained and viewing material meant to be engaging my HRV reaction can be a proxy for how much I enjoyed and connected with what I was seeing.
As I find note taking boring, I see a few potential techniques to develop here. Perhaps when interviewing candidates for a role I no longer need to take notes, but can simply compare HRV readings after the discussions. Or I can rent myself out as a speech meter and simply sit in rehearsal presentations and upload the HRV data afterward. When people ask “What did you think?” I can say “I don’t know, look at the data and you tell me!”